kubenetes创建编排：yaml/json

创建一个简单的pod，只含有一个tomcat

1.搭建好kubenetes的整套环境

2.写一个编排yaml格式

kubenetes里面的创建service、rc、pod都是这种形式(另外一种是json)

根据名字基本也不难猜到是什么意思。

apiVersion: v1
kind: Pod
metadata:
name: example-app
labels:
app: example-app
version: v1
spec:
containers:
- name: java
image: tomcat-1
ports:
- containerPort: 8080

下面配置的container表示创建pod的时候里面有这些container，如果不存在则会自动帮你创建container

container不用解释了吧，把它当做一个应用就行.

3.启动一个pod

kubectl create -f test.yaml

完成。如果报错参考

http://blog.csdn.net/jinzhencs/article/details/51435020

附：JSON格式

{
"kind": "Pod",
"apiVersion": "v1",
"metadata": {
"name": "demo",
"labels": {
"name": "demo",
"version": "v1"
}
},
"spec": {
"containers": [
{
"name": "tomcat-test",
"image": "index.tenxcloud.com/tenxcloud/tomcat",
"ports": [
{
"containerPort": 8100

}
]
},
{
"name": "mysql-1", // 不能写成 mysql.abc.com
"image": "mysql-imagexxxxxxxxx", // 要确定有此镜像，可以是本机的或者是远程仓库的
"ports": [
{
"containerPort": 8105

}
]
}
]
}
}

创建包含多个container的pod、rc、service

1.创建pod

-demo-pod.json

{
"kind": "Pod",                 //类型 Pod、Service、ReplicationController 注意首字母必须大写
"apiVersion": "v1",
"metadata": {                  //pod本身的信息
"name": "tomcat-ming-pod", //pod的名称
"labels": {                //pod的标签，用于kubenetes其他组件来标识这个pod
"name": "tomcat-ming-pod",
"version": "v1"
}
},
"spec": {
"containers": [            //这个pod包含的docker container，一个pod可以由多个container组成
{
"name": "tomcat-container-1", //第一个container的name
"image": "tomcat-1",          //镜像，可以是本机已有的或者远程仓库的
"ports": [
{
"containerPort": 8080//
//"hostPort":5000    //把这个容器本身暴露在外网的端口，一般不这么做
//都是通过service把服务暴露的，而不是容器本身暴露
}
]
}，
{
//第二个container的配置，例如mysql、redis
}
]
}
}

2.创建service使得外部能够访问pod内的服务

-demo-service.json

{
"kind": "Service",     //类型:service
"apiVersion": "v1",
"metadata": {          //service本身的一些信息
"name": "tomcat-ming-service",
"labels": {        //service的标签 用于其他组件标识定位到这个service 一般没啥用
"name": "tomcat-ming-service"
}
},
"spec": {              //主要配置 用于配置service代理的端口转向哪个pod的服务
"type": "NodePort",//类型:ip:port形式暴露服务
"ports":           //表明可以一次代理多个ip:port，目前只需要代理一个端口即可
//一般一整套系统也只应该有一个出口，比如haproxy或是tomcat
[{
"port": 8080,  //service本身的port，并没什么用，无视
"targetPort":8080,//目标container的port
"nodePort":32016  //外网访问的端口，此处有坑，范围必须是30000-32000/35000具体忘记了
}],
"selector": {         //筛选pod
"name": "tomcat-ming-pod", //根据之前定义的pod的标签里面的name
"version": "v1"            //还可以自定义一些键值对.
}
}
}

目前这里我有一个问题，就是一个pod如果有2个tomcat，那么container内部都是8080，

那么service这里的targetPort 8080最终会指向谁？

但可能是我的无稽之谈，因为一个pod内应该是几个不同的系统，比如

haproxy、tomcat、redis、mysql，由此他们的container启动的端口也就不会有冲突。

targetPort自然不会有冲突。这个问题先pass

补充:

同一个pod内不允许端口重复

附上目前我用的rc模板(使用freemark)

{
"kind": "ReplicationController",
"apiVersion": "v1",
"metadata": {
"name": "${stackName}",
"namespace":"${namespace}",
"labels": {
"release": "${releaseUuid}",
"appName": "${appName}",
"deployType": "${deployType}",
"stackName": "${stackName}",
<#list containerList as containerInfo>
"${containerInfo.microServiceName}-version": "${containerInfo.version}"
<#if containerInfo_has_next>,</#if></#list>
}
},
"spec": {
"replicas": ${replicas},
"template": {
"metadata": {
"name": "${stackName}",
"labels": {
"release": "${releaseUuid}",
"appName": "${appName}",
"deployType": "${deployType}",
"stackName": "${stackName}",
<#list containerList as containerInfo>
"${containerInfo.microServiceName}-version": "${containerInfo.version}"
<#if containerInfo_has_next>,</#if></#list>
}
},
"spec": {
"volumes":
[{
"name": "ulog",
"hostPath":
{
"path": "/var/logs/ulog"
}
},
{
"name": "serverlog",
"hostPath":
{
"path": "/var/logs/serverlogs"
}
}],
"dnsPolicy": "Default",
"imagePullSecrets": [
<#list secretList as secret>{
"name": "${secret}"
}
<#if secret_has_next>,</#if>
</#list>
],
"containers": [
<#list containerList as containerInfo>{
"name": "${containerInfo.microServiceName}",
"image": "${containerInfo.imageUrl}",
"imagePullPolicy": "Always",
<#if containerInfo.portList??>
"ports": [
<#list containerInfo.portList as portInfo>{
"containerPort":${portInfo.targetPort?c},
"protocol":"${portInfo.protocol}"
<#if portInfo.hostPort??>
,
"hostPort":"${portInfo.hostPort?c}"
</#if>
}
<#if portInfo_has_next>,</#if>
</#list>
],
</#if>
<#if containerInfo.envList??>
"env": [
<#list containerInfo.envList as envInfo>{
"name": "${envInfo.name}",
"value": "${envInfo.value}"
}
<#if envInfo_has_next>,</#if>
</#list>
],
</#if>
"volumeMounts": [
{
"mountPath": "/var/logs/k8s/serverlogs",
"name": "serverlog"
},
{
"mountPath": "/var/logs/k8s/ulog",
"name": "ulog"
}
],
"resources": {
"requests":{
<#if containerInfo.cpu??>
"cpu": "${containerInfo.cpu}"
</#if>
<#if containerInfo.cpu??>
<#if containerInfo.memory??>
,
</#if>
</#if>
<#if containerInfo.memory??>
"memory": "${containerInfo.memory}"
</#if>
}
}
}<#if containerInfo_has_next>,</#if></#list>
]
}
}
}
}